1. Field of the Invention
This invention generally relates to assembly of components using woven preforms and particularly relates to assembly of components into structural joints using adhesive-infused preforms.
2. Description of the Prior Art
Typically, laminating resins are used as the matrix material in woven textiles, this also being true for woven preforms used to connect components made of composites or other materials. An example of a commonly-used laminating resin is 977-3, available from Cytec Industries, Inc., of West Paterson, N.J. The laminating resin is infused into a textile product and is cured to form a polymer matrix in the finished composite component. When assembling a joint using a preform, the preform may be co-cured along with uncured composite components or the components may be cured prior to assembly using an uncured preform. Because of the inferior bonding characteristics of laminating resins, an layer of adhesive is placed between the preform and the components. Generally, an adhesive film is used, which is expensive and adds to fabrication time.
To achieve proper bonding when using adhesive film between pre-cured components, special attention must be paid to the interface at the adhesive layer. This bond line is critical, and, where two surfaces are brought together, the distance between the surfaces must be within a critical tolerance to ensure a proper bonding layer. The thickness of the adhesives are usually about 0.015xe2x80x3 thick with a bond layer tolerance of +/xe2x88x920.005xe2x80x3.
Therefore, a need exists for an improved method that reduces the steps in assembly and provides for a stronger joint when joining components using a woven preform. A further need exists for a method of joining components in a structural joint that provides for a larger dimensional tolerance between components when using an adhesive at the bond line.
A method uses a three-dimensional, woven preform to assemble two components. The woven preform is infused with an adhesive, and at least one surface of the preform is bonded to at least one surface of one of the components using the adhesive within the preform. The other of the components is attached to the preform, and this may occur with fasteners after the adhesive is cured or by bonding the second component to the preform with the adhesive. Use of an adhesive, instead of a resin, creates a stronger joint, especially with fiber-reinforcement of the adhesive. The thickness of the compressible, three-dimensional weave provides for a larger dimensional tolerance at each bond line.